This invention concerns in general a headband having at least two different adjustment features. In particular, a first adjustment feature enables a user to make coarse adjustments of the axial distance between selected portions of the headband, while a second adjustment feature permits the user to make fine adjustments of such axial distance.
The use of headbands to support electrical or mechanical equipment (such as earphones, microphones or flashlights) has long been known for advantageously permitting "hands-off" operation of such electrical and mechanical equipment. In general, conventional headbands such as those which support an earphone element for either one or both ears of the user usually constitute a "C-clamp" type device comprising a spring, the tension of which applies pressure to the head of the user so as to hold a headset on the user's head. This spring tension is usually somewhat adjustable by flexing the elements which comprise the headband.
A general problem of such prior art is that a user experiences difficulty in precisely adjusting the amount of tension of the headband gripping his head. Often a user is painfully aware of such limitations of a conventional headset in that the pressure exerted on his head by the headset is too great or too little to be satisfactory. The pain of excessive pressure may be compounded by the necessity of wearing the headband for lengthy periods of time. If the pressure is too great, discomfort, lack of concentration and even headaches may be caused. The seriousness of such disadvantages is directly related to the type of activity in which the user is engaged. For example, if a user is an airplane pilot, air traffic controller, or even an astronaut, loss of concentration can have serious and perhaps deadly consequences.
However, if a user attempts to loosen the headset to relieve such excessive pressure, and only a coarse adjustment is present, the user is likely to decrease the pressure to the point where slippage of the headset can occur. It is possible for such slippage to cause loss of communications if the earphone element becomes separated from the user's ear. Such an occurrence can have adverse consequences equal to the loss of concentration, etc. consequences stated above.
It is possible that some of the foregoing problems with over-pressure and under-pressure fittings could be partially reduced by custom fitting of every headset for each individual user, but such a solution is highly impractical, if not literally impossible, and very costly in the aggregate, as understood without further explanation.
Accordingly, there has been a long felt need for headsets which can be mass manufactured, but yet easily adjusted to fit an individual user, taking into account both the physical dimensions and personal tastes of those wearing such headsets.
Some attempts at solving this problem are known. For example, the U.S. Pat. No. (1,546,567) to Childress discloses a head support for radio receivers. The head support includes a flexible headband which rests across the head of a user, and which is associated with a basically rectangular metal framework mounted thereabove. In the center of such framework is a turn-buckle which through alternate rotation causes the metal framework to expand and contract in such a manner that pivot points formed at each end of the headband cause the radio receiver elements of the Childress device to rock back and forth, thereby providing some measure of adjustment with respect to a user's head. As stated specifically in lines 96-108 of page 1 of Childress, the angle of rest of the receivers on a user's ears is rocked back and forth by turning of the turn-buckle. However, there is no change in the headband pressure on the user's head because the headband 5 of Childress does not change once it conforms to a user's head. Also, there is no change in the basic axial distance between the two radio receivers of the Childress head support device.
German Patent No. 3207098 to Gorike discloses adjustable earphone speaker elements, which adjust by virtue of their retractability into a headset. There is no suggestion that such adjustment enables minimization of pressure from a headband, or selected fine variation of the axial distance between end elements of the headband. The U.S. Pat. No. 4,409,442 to Kamimura is similar to the German Gorike reference in that there is no disclosure of any headband adjustments, only selected positioning of retractable ear piece members. Likewise, the U.S. Pat. No. 4,455,457 to Akira is similar to the Kamimura reference, but additionally provides a locking feature for the retractable elements by using a lobe element and a recess.
U.S. Pat. No. 3,225,147 to Dollinger discloses a coarse set screw adjustment for a headband which holds a conventional telephone handset against the ear and mouth of a user. The coarse set screw adjustment also permits folding of the headband. There is no suggestion of any two-way adjustment, particular including both coarse and fine adjustments for headband pressure or axial distance between certain headband elements. Likewise, the U.S. Pat. Nos. (3,884,240) to Gillman and (947,153) to Forth which generally disclose set screw mechanisms and rack and pinion mechanisms fail to suggest particular features of the present invention which are discussed in greater detail hereinbelow.